Depth perception for a three dimensional television (3D TV) is provided by capturing two views, one for the left eye and other for the right eye. These two views are compressed and sent over various networks or stored on storage media. A decoder decodes the two views and sends the decoded video to the 3D TV for display. The two views are known to be either merged into a single video frame (e.g., checker board pattern, left and right, or top and bottom panels) or kept separate. The views are known to be displayed using a time sequential format in which one eye view follows another eye view in an alternating format.
In order to view 3D content, an end consumer uses a shutter glasses such as phase-shutter glasses. The shutter glasses must allow each eye to observe the corresponding image at the corresponding time. For example, the left side of the shutter glasses is open when the left eye image is displayed and the right side is closed, which allows the left eye to view the image but not the right eye. Similarly, the right side of the shutter glasses is open when the right eye image is displayed and the left side is closed, which allows the right eye to view the image but not the left eye.
The 3D TVs are known to emit a shutter control signal that is synchronized with the right or left eye image being displayed. However, this shutter control signal is known to be individualized for each 3D TV according to the manufacturer and, in some instances, the model of the 3D TV. The shutter control signal is not functional for 3D TVs from other manufacturers without a standardized protocol. Also, the shutter control signal is not functional for a non-3D-ready TV. Furthermore, it is difficult to provide an accurate shutter control signal from a set top box (STB) or another device outside the non-3D TV because of a timing difference due to differences in internal buffering, transmission delay, image processing delay etc on the end video rendering device. For example, the displayed frame at the TV lags behind the frame output from the STB for some amount of time, which varies from one display device to another display device, and thus, the shutter control signal emitted from the STB or devices other than the TV itself would not synchronize with the left or right eye image displayed on the TV. This can cause crosstalk of images because of the offset in left/right eye timing that in turn degrades or destroys the 3D effect.